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    <meta charset="UTF-8">
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    <title>Document</title>
</head>

<body>
<script>
    // 1. 类的继承
    // class Father {
    //     constructor() {

    //     }
    //     money() {
    //         console.log(100);

    //     }
    // }
    // class Son extends Father {

    // }
    // var son = new Son();
    // son.money();
    class Father {
        constructor(x, y) {
            this.x = x;
            this.y = y;
        }

        sum() {
            console.log(this.x + this.y);

        }
    }

    class Son extends Father {
        constructor(x, y) {
            super(x, y); //调用了父类中的构造函数
        }
    }

    const son = new Son(1, 2);
    const son1 = new Son(11, 22);
    son.sum();
    son1.sum();
</script>
</body>

</html>
